AUTOMOTIVE

Over 1,000 pulsars are known to astrophysicists since the first was detected in 1967. But it remains an unusual discovery because a pulsar is a small, dense, rotating star emitting radio waves, elusive and hard to pin down in astro searches. Since 2001, astrophysicists from India and abroad have kept a celestial vigil at the GMRT campus. Spread over 20 km near Khodad village in rural Pune with 30 giant parabolic antennae— each about 45 m in diameter or the size of a small swimming pool, this one is the world’s most powerful radio telescope in metre wavelength. Twenty per cent of GMRT’s observation time goes into the study of pulsars, and one-third of this time is used by foreign observers, who apply for sanction every six months to GMRT’s time allocation committee. ‘‘We’ve found a binary millisecond pulsar,’’ says Nityanand. It means this pulsar—10 kms in size—rotates a dizzying 200 times every second in an unusually elongated orbit instead of a circular orbit. Its width is about half its length. ‘‘We were searching among particular star clusters,’’ says Nityanand. The pulsar was spotted near the centre of a star cluster called NGC1851. The location was pinned down using GMRT’s capability of making a ‘‘picture’’ with radio waves, by combining signals from the 30 antennae. For now, until an international paper is published on the subject, NCRA cautiously terms the find ‘‘interesting and a sign of things to come.’’